Delayed Interval Delivery of the Twin

The delayed interval delivery of twins (DIDT) is a rare obstetric condition. With advancements in assisted reproductive technology, twin pregnancy complications have become increasingly prominent, necessitating urgent clinical attention.1 However, a unified management standard for twin pregnancies following the loss of one fetus remains elusive to date.2 In this correspondence, we present three cases of DIDT and conduct a literature review to summarize management strategies for twin pregnancies when the first twin is delivered prematurely during early gestation. Written informed consent was obtained from all patients involved. The first case was a 33-year-old woman who underwent in vitro fertilization (IVF) and presented with preterm premature rupture of membranes (PPROM) at 18+5 weeks of gestation. Despite her desire to continue the pregnancy, abdominal pain and mild uterine contractions led to the delivery of a non-viable fetus (twin A) weighing 290 grams at 19+5 weeks. Following delivery, vaginal bleeding, and uterine contractions ceased within an hour, while twin B remained intrauterine with a normal fetal heart rate. The patient underwent cervical cerclage, followed by postoperative broad-spectrum antibiotics and symptomatic treatment. At 29 weeks, a healthy male infant weighing 1160 grams was delivered, and the maternal postpartum period was uncomplicated (Table 1). The second case was a 35-year-old woman, 20 weeks and 1 day pregnant after IVF-embryo transfer (IVF-EF), who was admitted due to PPROM. At 20+3 weeks, a non-viable fetus (twin A) weighing 309 grams was delivered vaginally. Post-delivery, antibiotics were administered to prevent infection, and indomethacin was used for 48 hours to inhibit uterine contractions. Oral progesterone was prescribed for fetal protection. Given her desire to continue the pregnancy, an emergency McDonald cervical cerclage was performed vaginally the day after delivery. At 24+4 weeks, a healthy male infant weighing 904 grams was delivered vaginally and is thriving. The third case was a 40-year-old woman admitted after IVF-ET due to irregular lower abdominal tightness. At 18+5 weeks of gestation, she experienced fluid leakage indicative of PPROM. Despite the patient and her family’s request to delay delivery, twin A, a female infant with an Apgar score of 0-1-0, was delivered vaginally three days later and did not survive. Discussion When a twin pregnancy patient delivers a portion of the fetus (Twin A) due to maternal or fetal factors, while the remaining fetus (Twin B) may experience severe premature complications or even death, DIDT may be considered. Currently, the vast majority of DIDT cases involve twin pregnancies with double chorionic and double amniotic sacs, and there are only a few successful instances in single chorionic and double amniotic sac twins. Lao et al.3 reported that natural miscarriage of Twin A before 24 weeks of gestation allows for DIDT on Twin B, increasing Twin B’s survival rate to 34%-43%. However, some studies have also indicated that DIDT may lead to serious complications for both the mother and fetus, such as placental abruption, severe preeclampsia, and chorioamnionitis.4 Our case series suggests that DIDT can extend Twin B’s gestational age to some extent and significantly improve its perinatal outcomes. Table 1 - Clinical characteristics and outcomes of three IVF-ET twin pregnancies with delayed delivery. Category Case 1 Case 2 Case 3 Maternal information Mode of conception IVF-ET IVF-ET IVF-ET Age (years) 33 35 40 Reproductive history G1P0L0A0* G1P0L0A0* G3P1L1A1* First twin delivery Cause of admission PPROM PPROM + Cervical incompetence PPROM + Cervical incompetence GA (weeks) 20+1 20+3 19+3 Birth type Vaginal birth Vaginal birth Vaginal birth Birth weight (g) 290 309 275 APGAR score 0-0-0 0-2-0 0-0-0 Survival outcome No No No Management and second twin delivery Cervical cerclage Yes Yes No Interval between deliveries (days)† 62 29 3 GA (weeks) 29 24+4 19+6 Birth type Vaginal birth Vaginal birth Vaginal birth Birth weight (g) 1160 904 280 APGAR score 7-8-8 2-5-6 0-1-0 Survival outcome Yes Yes No *G1P0L0A0 means one pregnancy, no live births, no losses; G3P1L1A1 means three pregnancies, one full-term birth, one living child, and one abortion.†Interval between deliveries means the number of days between the delivery of the first and second twin.APGAR score: A quick assessment of a newborn’s condition immediately after birth, including Appearance, Pulse, Grimace, Activity, and Respiration; GA: Gestational age; IVF-ET: In vitro fertilization-embryo transfer; PPROM: Preterm premature rupture of membranes. Infection is a crucial factor affecting the success of DIDT. To prevent infection, it is generally advisable to avoid perineal incision during the delivery of Twin A and to administer broad-spectrum antibiotics as soon as possible after delivery.5 In our DIDT cases, broad-spectrum antibiotics should be routinely prescribed postoperatively, and the patient’s infection signs and symptoms should be closely monitored, including daily temperature checks, C-reactive protein levels, and postpartum placental pathology results. Numerous literature reports suggest that delayed delivery can prolong Twin B’s gestational age, increase the birth weight of newborns, and improve survival rates.4–6 In our cases, after 2 years of follow-up post-surgery, no abnormalities in the physical and intellectual development of the newborns were observed. Maternal outcomes were primarily related to infectious complications. The gestational age recommendations for glucocorticoids to promote fetal lung maturation vary among guidelines. The American College of Obstetricians and Gynecologists (ACOG) recommends their use for those at risk of premature birth between 24 and 34 weeks of gestation, with optimal benefits observed within 48 hours to 7 days after administration, which can help improve neonatal outcomes.7 In our cases, when pregnant women were over 24 weeks and at risk of premature birth, we urgently administered dexamethasone to promote fetal lung maturation and magnesium sulfate to protect fetal brain nerves. Two newborns were followed up until age 2, and no abnormalities in motor or intellectual development were found. Due to the absence of prospective, multicenter clinical studies on cervical cerclage in DIDT, there has been debate regarding its implementation. In our cases, the combination of DIDT and cervical cerclage was feasible, safe, and effective. Timely cervical cerclage could significantly prolong Twin B’s gestational age, but the timing of the procedure depended on the mother’s circumstances. Before cerclage, a comprehensive evaluation was conducted to exclude cervical and vaginal infections. However, further research involving larger patient populations in randomized trials is required.