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King Edward Memorial Hospital
Obstetrics & Gynaecology
Contents
Complications (early pregnancy): Assess / diagnose ......... 3
Assessment ............................................................................................................ 3
Bleeding / pain algorithm (early pregnancy) ........................ 7
Bleeding (vaginal) and a viable intrauterine pregnancy...... 8
Procedure ............................................................................................................... 8
Early gestational sac: Management of ................................ 10
Ultrasound features of EGS .................................................................................. 11 Management ......................................................................................................... 11
Gestational Trophoblast Disease / Hydatidiform mole ...... 12
Risk factors ........................................................................................................... 13 Classification ......................................................................................................... 14 Pre-malignant trophoblast disease ........................................................................ 14 Malignant Trophoblast Disease ............................................................................. 15 Management of GTD............................................................................................. 16 GTD follow up flowchart ........................................................................................ 21
Absence of chorionic villi in products of conception &
negative laparoscopy ........................................................... 22
Nausea and vomiting in pregnancy / hyperemesis
gravidarum ............................................................................. 23
Hyperemesis: Management in the home............................................................... 31
CLINICAL PRACTICE GUIDELINE
Pregnancy care: First trimester complications
This document should be read in conjunction with the Disclaimer
- Ectopic pregnancy
- Ectopic pregnancy: Expectant management
- Ectopic pregnancy: Medical management
- Ectopic pregnancy: Surgical management
- Ectopic pregnancy: Caesarean section scar
- Miscarriage
- Early Pregnancy Assessment Service (EPAS)
- Children 13 years and under: Products of conception
- References and resources
Aspect Considerations Rationale
Pain ^ Location, radiation, nature
Constant or intermittent Provoking or relieving factors Presence of shoulder tip pain
Vaginal
bleeding
Onset, nature (heavy/spotting) of bleeding Last menstrual period – duration and nature Passage of tissue or products of conception
Vaginal bleeding can be associated with a complication of early pregnancy or identify another cause
Reproductive
history
Sexually active Current contraception use History of recent assisted contraception If possibility of pregnancy – investigations performed, presence of symptoms of pregnancy
Obstetric &
gynaecological
history
Number of pregnancies (gravida) – live births, miscarriages and terminations
- details of gestation and treatments Number and nature of previous births Previous ectopic pregnancies Recent dilatation and curettage Pap smear history Previous pelvic inflammatory disease (PID) Previous infertility Sexually transmitted infections
To identify high risk factors for ectopic pregnancy or other conditions that may require further investigation, observation or intervention.
Risk factors for ectopic pregnancy: Multiple sexual partners Previous sterilisation or reversal of sterilisation Early age of sexual intercourse and/or Presence of IUD and assisted contraception
Complete the assessment with a thorough medical, surgical, social and family history
Examination and investigations
After completing the above history taking it is important to do a physical examination and carry out the appropriate investigations.
Examination ^ Abdominal examination^ –
tenderness and distention PV blood loss on pad Vaginal examination
- Speculum – site and amount of bleeding, cervical os (ectropion, or products of conception visible)
- Bimanual – cervical excitation, cervix open or closed, adnexal masses, size of the uterus An open cervix can only be assessed by digital examination not speculum [Recommendation Mar 2019]
To exclude an acute abdomen that might require urgent surgical intervention
Vaginal examination should be individualised as clinically appropriate. If products are visible in the os, they should be removed and sent for histopathology
Investigations ^ Obtain IV access with a
14gauge cannula and commence IV therapy if indicated β-HCG – urine and quantitative β-HCG, serial β- HCG if relevant FBC, Coagulation Studies, UEC (if significant bleeding is present) Check Rhesus D antigen and antibody status if a negative blood group
Consider history taken and if screening is required for blood borne and infectious diseases i.e. Chlamydia, Hep B/C, HIV Consider serum progesterone levels with USS as it may assist with PUL
All women of reproductive age with signs of abdominal pain or vaginal bleeding should have a pregnancy test. A single β-HCG indicates when an intrauterine pregnancy should be visualised on USS. Serial β-HCG is useful in the diagnosis of an asymptomatic ectopic pregnancy, or to assess viability of a pregnancy. All women requiring surgical uterine evacuation should be screened for Chlamydia Trachomatis – as it places women at an increased risk of PID. A serum progesterone level <25nmol/L in conjunction with a PUL are confirmed to be
Bleeding / pain algorithm (early pregnancy)
** Ultrasound can only diagnose complete miscarriage if an intrauterine pregnancy has been previously proven or products of conception have definitely been identified. Abbreviation - Pregnancy of unknown location (PUL)
Is pregnancy test positive?
Is intrauterine gestation sac seen on Ultrasound?
Is foetal pole seen? Is an adnexal mass seen?
Is foetal heart present?
Is Mean Sac Diameter (MSD) ≤25mm?
Is Crown Rump Length (CRL) ≥7mm?
Have Products of Conception (POC) definitely been seen by staff and sent for histology?
Yes, and no POC in uterus
Yes, but POC remain in uterus
No , and no POC in uterus
Investigations for Dysfunctional Uterine Bleeding Refer accordingly
N
Y
Y N
Y N
Y N
Y N
Y N
Viable intra uterine pregnancy
*Missed miscarriage
*Missed miscarriage
*Early Gestational Sac
Ectopic pregnancy
Complete mis- carriage* *****
Incomplete mis- carriage
PUL-
Needs follow up including BhCG until ≤ 5
Y N
*Record CRL / MSD if seen.^1 Before making diagnosis, seek 2nd opinion^2 &/or repeat scan in: >7days^2 (if transvaginal scan used) or >2wks (if transabdominal scan used).^1
Competent Registrar to assess all patients with PUL prior to discharge.
Bleeding (vaginal) and a viable intrauterine pregnancy
Background
Threatened miscarriage is defined as vaginal bleeding with or without abdominal pain, while the cervix is closed and the fetus is viable, inside the uterine cavity^9. Threatened miscarriage is the most common complication of early pregnancy occurring in 20% of women before 20 weeks gestation^8.
17 % of these women will continue to have further complications in pregnancy and are 2.6 times more likely to experience miscarriage at a later stage in the pregnancy^8.
Threatened miscarriage is associated with adverse maternal and perinatal outcomes^10. An increased risk of antepartum haemorrhage, pre-labour rupture of membranes, preterm delivery and intrauterine growth restriction has been documented^9. A UK study reports an association with malpresentation, manual removal of placenta and elective caesarean section^11.
Ultrasound has improved management by rapid confirmation of viability.^9 Transvaginal scanning has a positive predictive value of 98% in confirming diagnosis of complete miscarriage and should be used in assessment. The presence of a fetal heart has the most powerful association with pregnancy outcome. Studies have varied from indicating that at 3 - 5.3mm crown rump length (CRL) a viable fetus can be visualised^1. A 100% success rate has been found with a CRL of 6mm or more in diagnosing a viable pregnancy^1. Fetal bradycardia was a sign present in 1 in 3 pregnancies that were subsequently lost, whilst 7% of pregnancies that continued had bradycardia found on ultrasound^12.
Key points
- Manage all women with early pregnancy complications with respect and dignity, as this can cause significant distress^1. Provide comprehensive information throughout.
- Non-sensitised rhesus negative women should receive anti-D immunoglobulin for threatened miscarriages^8.
- In the case where a heartbeat is absent with a CRL of less than 7.0 mm or a mean gestational sac diameter of less than 25.0 mm measured on a single ultrasound, a repeat scan is recommended in 7 days if using transvaginal ultrasound or 14 days when transabdominal ultrasound is used^1.
Procedure
- Inform the woman of the assessment findings and diagnosis and provide reassurance.
- Give the woman the Information Sheet: Bleeding and/or Pain in Early Pregnancy.
- Refer to KEMH Clinical Guideline: Blood Group Management & Clinically Significant Antibodies (RhD Negative & RhD Positive Women) for guidance on checking the woman’s blood group and anti D immunoglobulin if rhesus negative.
Early gestational sac: Management of
Aim
To provide information on the management of an early gestational sac (EGS)
Background
The earliest definitive evidence of pregnancy visible on ultrasonography is the gestational sac. 4 weeks + 3 days is the earliest time to see a gestation sac eccentrically placed within the endometrium by a transvaginal ultrasound (TVS). By 5 weeks + 2 days the sac should be visualised, and should be 2-5 mm in diameter14, 15. 78.6% TVS after 49 days of gestation will diagnose pregnancy.^16 Very early gestational sac appears as fluid collection in central echogenic portion of the uterus; sometimes seen as the “double sac sign” or the “intradecidual sign”^15.
Ultrasound features with an empty gestational sac with mean diameter > 25mm and absent yolk sac with mean gestational sac diameter >20 mm are the threshold which has the most precise estimate of specificity for diagnosing early embryonic demise^17. A biochemical marker such as decline in human chorionic gonadotrophin (hCG) may predict miscarriage but does not preclude laboratory error or a physiological drop in hCG late in the first trimester. It is imperative to have a high specific test with zero false positive rate as diagnosis of fetal demise results in evacuation of the uterus^17. Ultrasound has lowered threshold values for visualisation of gestational sac^18. Disproportionately small or non-visible embryo within an enlarged amnion is a good marker for a failed pregnancy^14. Theoretically cardiac activity should be evident when embryo is over 2mm, but in 5-10% of cases where this has been documented pregnancy outcome was normal^19.
The presentation of women with an “empty sac” is common; with up to 10% of women attending health centres with uncertain viability in pregnancy^8. Early normal pregnancies always show a gestational sac but no detectable embryo during a brief but finite stage of early development^14. Once a gestational sac has been documented subsequent loss of viability remain around 11%, there is no difference between gestational sac diameter when compared with pregnancy outcome^19. If an embryo has developed up to 5 mm length, loss of viability occurs in 7.2% of cases^19. Persistence of yolk sac has been found inside the gestational sac after embryonic demise^19. 10-20% of ectopic pregnancies have an intrauterine pseudo gestational sac and it is important to be aware of the rare possibility of concurrent intrauterine and extra uterine pregnancy^20.
Definitions
Intrauterine sac : < 20mm mean diameter with no obvious yolk sac or fetus.
Uncertain viability: An intrauterine gestational sac (IUGS) of <25mm in mean diameter with no obvious yolk sac, or the presence of a fetus or fetal echo of <7mm CRL with no fetal heartbeat. A repeat scan at a minimum interval of 1 week is necessary^8.
Missed miscarriage: An empty IUGS with a mean diameter ≥25mm or CRL ≥7mm with no fetal heart is diagnosis of missed miscarriage
Ultrasound features of EGS
It is seen as a round, anechoic structure with an echogenic rim. When it first appears on ultrasonic imaging, the gestational sac is surrounded by a thickened decidua. This perimeter then becomes a distinct “double ring” (Also known as the “double decidual sign”). It is eccentrically placed i.e. it remains within a thickened decidua on one side of the uterine cavity. It is typically located in the fundus on the posterior wall. Mean Sac Diameter (MSD) is a useful indicator of GA before CRL measurement is available.
Management
- Early gestation sac needs to be differentiated from a pseudo gestation sac.
- A follow up scan should be arranged in 7-10 days if there is certainty about the diagnosis of EGS or in 3 days to assess the growth of the sac if the diagnosis is uncertain. A healthy gestational sac grows by 1.2mm / day^19.
- A yolk sac will usually be visible at the next scan in a normal pregnancy.
- Correlation with quantitative hCG levels will be helpful although it should be remembered that following up every early gestational sac with serial measurements of hCG leads to increased patient anxiety.
- Give the woman information about when to attend for further medical review.
See also- section: Bleeding/Pain Algorithm (Early pregnancy)
Oestrogen and/or progestogen contraceptives (i.e COCP/implanon) may be used between evacuation of the molar pregnancy and prior to return to normality of BhCG levels. This does NOT appear to increase the risk of invasive mole or choriocarcinoma developing.21, 25, 26
- To minimise the risk of uterine perforation, insertion of an intrauterine device should be delayed for at least 6 weeks after evacuation of the uterus and after the BhCG levels have returned to normal.^21
- A diagnosis of persistent gestational trophoblastic disease, gestational choriocarcinoma and placental site trophoblastic tumours (PSTT) requires referral to the Gynaecologic Oncology team.
- For women who conceive again after having a molar pregnancy, there is a 1: chance of recurrence. An ultrasound scan early in pregnancy at 6 weeks gestation is recommended. Also, a BhCG level should be completed 6 weeks after the conclusion of any future pregnancy regardless of the outcome (i.e. miscarriage, termination, or delivery).^21
- The patient’s general practitioner (GP) should be notified of the diagnosis of gestational trophoblastic disease and a discharge letter should be sent on conclusion of treatment and/or follow up.
Background^27
Gestational Trophoblast Disease (GTD) is a rare group of placental related disorders derived from a pregnancy. The incidence of molar pregnancies is in the order of 1:200-1000 pregnancies. They form a spectrum of illnesses from hydatidiform mole (complete and partial) to choriocarcinoma and because of their secretion of human chorionic gonadotrophin (hCG), they can be accurately monitored. They have cure rates approaching almost 100%. The types of trophoblast disease range from the usually benign partial and complete molar pregnancy through to invasive mole, malignant choriocarcinoma and placental site trophoblast tumours.21, 24
The use of ultrasound in early pregnancy has led to the earlier diagnosis of molar pregnancy, as opposed to the common clinical presentations of irregular vaginal bleeding, hyperemesis, excessive uterine enlargement, early failed pregnancy or persistent vaginal bleeding following a completed pregnancy. Rarer presentations may include hyperthyroidism, early onset pre-eclampsia or the presence of theca lutein cysts. HCG levels greater than two multiples of the median may also contribute to the diagnosis.21, 22
Gestational trophoblastic neoplasia (GTN) is a term used to describe GTD requiring chemotherapy or excisional treatment because of the persistence of hCG or the presence of metastases. GTN follow hydatidiform mole (60%), previous miscarriage / abortion (30%), normal pregnancy or ectopic gestation (10%).^21
Risk factors
Extremes of reproductive age^21 Age 45 years and over Age 16 years and under
Previous GTD Woman from Asia have a higher incidence of GTD (1:390) compared to non- Asian women (1:750).^21 There may be a higher incidence of molar pregnancies in Africa and Asia. However, the varying standards in the frequency and accuracy of histopathology makes it difficult to make accurate comparisons.^28
Classification
The World Health Organisation classification divides trophoblast disease into the pre-malignant and malignant forms as shown below:
Pre-malignant Partial Molar Pregnancy Complete Molar Pregnancy Malignant Invasive mole (Persistent Gestational Trophoblastic Disease) Choriocarcinoma Placental site trophoblastic tumours (PSTT)
Pre-malignant trophoblast disease
Hydatidiform moles are separated into complete and partial moles based on genetic and histopathological features. In early pregnancy (less than 8-12 weeks gestation), it may be difficult to separate the complete and partial moles on microscopy alone, and other tests (ploidy, p57) will often be required to make the diagnosis.^21 Historically the relative incidence of partial and complete molar pregnancies has been reported as approximately 3:1000 and 1: 1000, respectively.^24
Partial mole
Partial moles are usually triploid with 2 sets of paternal and 1 set of maternal chromosomes but may be tetraploid or mosaic in 10% of cases^24.
Macroscopically partial moles may resemble the normal products of conception as they contain embryonic or fetal material such as fetal red blood cells. As a result, the diagnosis of partial mole can often be missed after an apparently straightforward miscarriage or termination.
Partial moles rarely become malignant with an overall risk of 0.5% requiring chemotherapy after a partial mole. 22
Complete mole
Complete moles are diploid and androgenic in origin with no evidence of fetal tissue. The genetic material is entirely male in origin and results from the fertilisation of an empty ovum lacking maternal genes. The chromosome complement is most commonly 46XX, which results from one sperm that duplicates its DNA, or less frequently 46XX or 46XY from the presence of two different sperm in an empty ovum.^24 In contrast to a partial mole, a complete mole more frequently proceeds to invasive disease with 8-20% of patients requiring chemotherapy.21, 22
Management of GTD
NB: The Gynaecology Consultant rostered in EC at time of presentation must be notified for all suspected or confirmed molar pregnancies.
See GTD Follow-up Flowchart
Initial management for suspected molar pregnancy
- Perform initial blood tests for BhCG levels Blood group and Hold Full blood count (FBC)
- Arrange suction dilatation and curettage (D & C). Suction evacuation is recommended for complete and partial molar pregnancies. Consider evacuation under ultrasound guidance due to increased perforation risk with molar pregnancies. a. Notify consultant and/or registrar assigned to the theatre list and if possible book case at the beginning of the D&C list due to excessive bleeding risk. b. Ensure that there is a current G&H c. Misoprostol may be given prior to surgery^23
- Avoid the use of oxytocics until after uterine evacuation has been completed. This reduces the risk of causing trophoblastic embolism from the placental bed and disseminated disease.
- Send all products of conception for histology examination and consider cytogenetics
- Administer RhD immunoglobulin to Rh-negative patients after surgery
6. Chase histopathology results in EC. This should be done by the EC registrar.
7. Provide initial patient education and provision of information brochures.
8. Provide information about pregnancy loss services and/or referral to
psychological medicine if required.
Management of ‘confirmed’ complete and partial mole
- Ring patient and arrange scheduled review in EC to discuss the diagnosis and provide patient information as well as follow up requirements due to risk of persistent disease (Please refer to; “Follow Up” )
- Advise against pregnancy until end of surveillance period (Please refer to; “Contraception Advice ”)
- For complete moles ; arrange investigations including U&E, LFT, TFT, Coagulation profile and Chest X-ray.
Follow up
Following diagnosis of complete or partial mole (as confirmed on histopathology), patients should be followed with weekly serial serum hCG levels. The blood test can be performed at any Path West collection centre most convenient to the patient.
Ensure an “expect” sticker is placed on their medical files for weekly follow up. The EC registrar must review the hCG level and contact the patient with the result and follow up plan.
A negative (normal) quantitative BhCG level is <5 Iu/L.
Normalisation = three consecutive weekly normal BhCG levels (i.e. three consecutive weekly BhCG levels of ≤5 Iu/L).
If during follow up, there is an increase or plateauing hCG levels, please refer to; “ Management of Persistent Gestational Trophoblastic Disease”
1. Complete moles
Weekly quantitative hCG levels should be undertaken until 3 consecutive weekly normal levels are achieved. This is called normalisation. Then monthly levels should be performed for a further 6 months following normalisation. If during follow up and after initial normalisation, any level is > 5iu/L this must be reported to the consultant responsible for the woman’s care and discussed with gynaecology oncology.
2. Partial moles
Weekly quantitative hCG levels should be taken until 3 consecutive normal levels are achieved. This is called normalisation. If it takes less than 8 weeks to achieve normalisation the patient may be discharged without any further follow up. If normalisation takes more than 8 weeks to be achieved, the patient should have monthly quantitative hCG levels performed for a further 6 months from the time of normalisation. If during follow up and after the initial normalisation, any result is > 5iu/L this must be reported to the consultant responsible for the woman’s care and discussed with gynaecology oncology.
Histopathology “unable to exclude a molar pregnancy”
Manage as per a partial mole with weekly quantitative hCG levels.
Continue follow up while awaiting cytogenetic results. Seek advice from the pathologist and/or treating gynaecologist.
There may be a role for repeat suction D&C in selected cases for histological confirmation in difficult cases which may have problematic bleeding. However, there is an increased risk of perforation and excessive bleeding with repeat D&C. This should be discussed with the consultant Gynaecologist and/or gynaecology oncology.
See GTD follow-up flowchart within this section.
Contraception Advice:
Pregnancy should be avoided in the follow up period, and appropriate contraception can be utilised.
Women should be advised to use barrier contraception Oestrogen and/or progestogen contraceptives may be used between
FIGO anatomical staging of persistent gestational disease^33
Stage I Disease localised to uterus
Stage II Disease localised to the pelvis and adnexa
Stage III Pulmonary metastases
Stage IV Distant organ involvement (I.e. brain, liver, kidney, GI tract, spleen)
A modified World Health Organisation (WHO) prognostic system should be calculated to guide chemotherapy regime.
WHO prognostic score^34
- (^) End of antecedent pregnancy to chemotherapy.
The prognostic score predicts the potential for developing resistance to single-drug chemotherapy with MTX or actinomycin D (ActD). A score 0-6 is considered low risk and therefore a single chemotherapeutic agent is indicated. A score of 7 or greater indicates high risk of resistance and requires multi-agent chemotherapy regime^34.
NB: Prescribing of chemotherapeutic agents for GTN is done solely by the Gynaecology Oncology team. Multi agent chemotherapeutic regimes for resistant GTD or WHO high risk scoring patients requires specialised chemotherapeutic regime protocols that is organised by gynaecology oncology.
Methotrexate and folinic acid treatment regime :
See eviQ https://www.eviq.org.au/medical- oncology/gynaecological/gestational-trophoblastic-disease/668-gestational- trophoblastic-disease-low-risk-met
> Score
Prognostic factors 0 1 2 4
Age (yrs) <40 >39 - -
Antecedent pregnancy Mole Abortion Term -
Interval (months)* <4 4-6 7-12 >
Pre-treatment serum hCG (IU/L)
<10^3 103 -10^4 104 -10^5 >10^5
Number of metastases 0 1-4 5-8 >
Site of metastases Lung Spleen and Kidney
GI tract Brain and liver
Largest tumour mass, including uterine (cm)
Prior failed chemotherapy
Management of Gestational Trophoblastic Neoplasm:
- Inform patient of the diagnosis. Assess for signs and symptoms of metastatic disease
- All cases MUST be discussed with the treating Gynaecologist and referred to Gynaecology Oncology
- Arrange a metastatic screen
- Calculate FIGO staging and WHO prognostic risk score
GTN is very responsive to chemotherapy, and associated cure rates are greater than 90% even in women with metastatic disease^35. Women who receive chemotherapy are likely to experience menopause earlier by 1 year for single agent, and 3 years for multi-agent chemotherapy.22, 24, 30
In circumstances in which women have completed their families and when the disease is confined to the uterus, undergoing a hysterectomy can be an appropriate treatment option followed by close surveillance.^21
Management of a molar pregnancy with a coexisting viable twin pregnancy:
- Discuss with the Maternal Fetal Medicine (MFM) team and Gynaecology Oncology regarding management.
- Consider prenatal testing for karyotyping.
- Pregnancy outcomes in this situation may be poor:^36 a. 25% chance of a live birth b. 40% chance of early pregnancy loss c. 36% chance of preterm birth d. Up to 20% of these pregnancies are affected by pre-eclampsia
Post GTD care:
- Send a discharge letter to the GP. Provide information of discharge, the follow-up management and include management if the woman presents with a future pregnancy.
- Women should be counselled about what to do in their next pregnancy including an early ultrasound to exclude recurrence of GTD, and a BHCG level 6 weeks after the conclusion of any pregnancy event regardless of the outcome (i.e. miscarriage, termination, or delivery).^21
- Following chemotherapy for an invasive molar pregnancy, woman may be at increased risk of miscarriage or stillbirth if they fall pregnant within 12 months of completing multi-agent chemotherapy. Women should therefore be encouraged to avoid pregnancy for 12 months in this circumstance. 21, 22, 30 Fertility rate is not affected following chemotherapy.
See GTD Follow-up Flow chart below.
