Medical school teaching historically presented trisomy 13/18 as lethal, with survivors assumed to be mosaic; more recent evidence shows full trisomy cases can survive beyond one year with support.
Increased cesarean section risk in trisomy 13/18 may be related to smaller babies, placentas that don't tolerate labor well, or structural differences like omphalocele or enlarged head size.
Classical cesarean incisions (vertical on the uterus) do not heal as well as low transverse incisions and require preterm cesarean sections in all future pregnancies.
Even after a low-risk amniocentesis following high-risk NIPT, growth scans in the third trimester are recommended due to potential placental impact on fetal growth.
Mallory Hoffman, MD - 2024 Fetal Care Center Navigating Perinatal Care for Trisomy 13 & 18
▶Ep 3 · 0:36
quotewhen I was in medical school and residency, initially, I had always thought that the teaching was that trisomy 13 and trisomy 18 was a lethal diagnosis.↗
▶Ep 3 · 0:36
clinicalIncreased cesarean section risk in trisomy 13/18 may be related to smaller babies, placentas that don't tolerate labor well, or structural differences like omphalocele or enlarged head size.↗
▶Ep 3 · 0:36
epidemiologicalThe cesarean section rate for trisomy 13/18 pregnancies is 48%, compared to 32% in the general US population.↗
▶Ep 3 · 0:36
clinicalGrowth restriction and Doppler abnormalities may prompt earlier delivery timing.↗
▶Ep 3 · 0:36
clinicalNon-stress tests are recommended twice weekly to help detect fetal distress earlier, though they are not perfect for preventing stillbirth.↗
▶Ep 3 · 0:36
epidemiological13% of patients with trisomy 13 or trisomy 18 had preterm labor, not significantly different from the general population rate of about 10%.↗
▶Ep 3 · 0:36
clinicalPolyhydramnios in trisomy 13/18 can result from GI blockage, micrognathia preventing swallowing, or brain differences affecting swallowing signals.↗
▶Ep 3 · 0:36
clinicalAmnio-reduction uses a 20-gauge spinal needle and may remove several liters of amniotic fluid to relieve uterine stretch and prolong pregnancy.↗
▶Ep 3 · 0:36
epidemiologicalThe risk for stillbirth in trisomy 13/18 once in the third trimester is about 13%.↗
▶Ep 3 · 14:50
opinionPatients at a fetal care center are more selected toward those interested in interventions after delivery, compared to general MFM practices.↗
▶Ep 3 · 14:50
opinionFinancial limitations and late diagnosis can restrict access to out-of-state termination, leading more patients to choose comfort care.↗
▶Ep 3 · 14:50
quoteI don't think anybody knows what they would do until they were in that situation.↗
▶Ep 3 · 16:48
quotewe know a little bit more now that that's just not true, and that with more support, some of these kids can live longer even if they're not mosaic.↗
▶Ep 3 · 16:48
opinionMedical school teaching historically presented trisomy 13/18 as lethal, with survivors assumed to be mosaic; more recent evidence shows full trisomy cases can survive beyond one year with support.↗
▶Ep 3 · 16:48
opinionSome OB providers still counsel that comfort care is the only option for trisomy 13/18, reflecting outdated teaching that these are uniformly lethal diagnoses.↗
▶Ep 3 · 20:11
clinicalClassical cesarean incisions (vertical on the uterus) do not heal as well as low transverse incisions and require preterm cesarean sections in all future pregnancies.↗
▶Ep 3 · 20:11
clinicalRates of preeclampsia are higher in pregnancies with abnormal placentas, which is typical in trisomy 13/18.↗
▶Ep 3 · 22:05
opinionFamilies commonly change their minds multiple times during pregnancy and even during labor regarding their care preferences.↗
▶Ep 3 · 22:05
guidelineACOG supports cesarean section on maternal request, meaning any mother who requests a C-section can have one even without a fetal indication.↗
▶Ep 3 · 22:05
clinicalIn inductions with no fetal monitoring, the baby is often still born alive.↗
▶Ep 3 · 29:06
clinicalEven after a low-risk amniocentesis following high-risk NIPT, growth scans in the third trimester are recommended due to potential placental impact on fetal growth.↗
Mallory's statements about Trisomy 1821 statements
Mallory Hoffman, MD - 2024 Fetal Care Center Navigating Perinatal Care for Trisomy 13 & 18
▶Ep 3 · 0:36
epidemiological13% of patients with trisomy 13 or trisomy 18 had preterm labor, not significantly different from the general population rate of about 10%.↗
▶Ep 3 · 0:36
clinicalPolyhydramnios in trisomy 13/18 can result from GI blockage, micrognathia preventing swallowing, or brain differences affecting swallowing signals.↗
▶Ep 3 · 0:36
clinicalAmnio-reduction uses a 20-gauge spinal needle and may remove several liters of amniotic fluid to relieve uterine stretch and prolong pregnancy.↗
▶Ep 3 · 0:36
epidemiologicalThe risk for stillbirth in trisomy 13/18 once in the third trimester is about 13%.↗
▶Ep 3 · 0:36
clinicalNon-stress tests are recommended twice weekly to help detect fetal distress earlier, though they are not perfect for preventing stillbirth.↗
▶Ep 3 · 0:36
clinicalGrowth restriction and Doppler abnormalities may prompt earlier delivery timing.↗
▶Ep 3 · 0:36
epidemiologicalThe cesarean section rate for trisomy 13/18 pregnancies is 48%, compared to 32% in the general US population.↗
▶Ep 3 · 0:36
clinicalIncreased cesarean section risk in trisomy 13/18 may be related to smaller babies, placentas that don't tolerate labor well, or structural differences like omphalocele or enlarged head size.↗
▶Ep 3 · 0:36
quotewhen I was in medical school and residency, initially, I had always thought that the teaching was that trisomy 13 and trisomy 18 was a lethal diagnosis.↗
▶Ep 3 · 14:50
opinionFinancial limitations and late diagnosis can restrict access to out-of-state termination, leading more patients to choose comfort care.↗
▶Ep 3 · 14:50
quoteI don't think anybody knows what they would do until they were in that situation.↗
▶Ep 3 · 14:50
opinionPatients at a fetal care center are more selected toward those interested in interventions after delivery, compared to general MFM practices.↗
▶Ep 3 · 16:48
quotewe know a little bit more now that that's just not true, and that with more support, some of these kids can live longer even if they're not mosaic.↗
▶Ep 3 · 16:48
opinionMedical school teaching historically presented trisomy 13/18 as lethal, with survivors assumed to be mosaic; more recent evidence shows full trisomy cases can survive beyond one year with support.↗
▶Ep 3 · 16:48
opinionSome OB providers still counsel that comfort care is the only option for trisomy 13/18, reflecting outdated teaching that these are uniformly lethal diagnoses.↗
▶Ep 3 · 20:11
clinicalClassical cesarean incisions (vertical on the uterus) do not heal as well as low transverse incisions and require preterm cesarean sections in all future pregnancies.↗
▶Ep 3 · 20:11
clinicalRates of preeclampsia are higher in pregnancies with abnormal placentas, which is typical in trisomy 13/18.↗
▶Ep 3 · 22:05
opinionFamilies commonly change their minds multiple times during pregnancy and even during labor regarding their care preferences.↗
▶Ep 3 · 22:05
clinicalIn inductions with no fetal monitoring, the baby is often still born alive.↗
▶Ep 3 · 22:05
guidelineACOG supports cesarean section on maternal request, meaning any mother who requests a C-section can have one even without a fetal indication.↗
▶Ep 3 · 29:06
clinicalEven after a low-risk amniocentesis following high-risk NIPT, growth scans in the third trimester are recommended due to potential placental impact on fetal growth.↗
