Pregnancy management in 2nd trimester
Fetal surveillance in the first trimester if a dual marker is missed, it is very important to offer a triple or a quadruple marker test at 16 weeks of pregnancy. Amniocentesis has a role to play if dual marker or quadruple marker shows increased risk. An anomaly scan is done at 18 to 20 weeks of gestation. We need to monitor the structural and growth assessment by USG. We need to rule out certain specific congenital abnormalities so is fetal echocardiography necessary in all IVF/ICSI pregnancies after anatomic survey.
There are certain anomalies like renal agenesis or bowel obstruction which may be missed before 20 weeks and we must look for them during our second-trimester 24-week scan. The important next assessment is the cervical length assessment. This is really important. Now whether to do per vaginal examination or transvaginal sonography. Now PV is often subjective so PVS is a better mode of assessment. It is to be done between 16 and 24 weeks of gestation.
Now maternal evaluation, these patients are high-risk patients who come to us after ART, after doing ART. They may have an increased risk of hypertension, diabetes with advanced maternal age. There can be other associated comorbidities so let’s go one by one on what all things one must focus on during the second-trimester evaluation and why it is important. In vitro fertilization is associated with the onset and progression of preeclampsia. Why it happens because there is deficient trophoblastic invasion, defective placentation, we are transferring the conceptus through the cervix so there is an altered endometrial environment because of altered hormone levels. The formation of the chorion is initiated in vitro so there is an inherited difference in the nature of the placenta especially in frozen embryo transfer and oocyte donation cycle there is the absence of corpus luteum and subsequent deficiency of relaxin can disturb the maternal circulation which precipitates the development of preeclampsia. In OD cycles, there is immunological maladaptation or intolerance so these are the patients where we need to keep high suspicion for preeclampsia. Apart from first-trimester screening, you will be doing all the evaluations during the first trimester itself. One important thing is the spot urine protein creatinine ratio. This is better even in a dipstick test. If the dipstick shows more than 1+, rather than doing 24-hour monitoring you can do a spot urine protein to creatinine ratio, and if it is more than 30 mg/mmol that indicates that this patient can develop preeclampsia.
You can find out more details by enrolling in Pregnancy Management after ART – Is it different? by Dr. Garima Sharma (MS, DNB OBGY, FRM) & Dr. Aditi Trivedi( DNB OBGY, FRM) here, https://docmode.org/pregnancy-management-after-art-is-it-different-26-june-2021/