SUDANESE JOURNAL OF PAEDIATRICS

2021; Vol 21, Issue No. 2

IMAGE

Coexisting molar and live twin pregnancy

Roshni Anand (1), Sumit Kumar (1), Sonal Saran (1)

(1) Department of Radiodiagnosis, All India Institute of Medical Sciences, Rishikesh, India

Correspondence to:

Sonal Saran

Assistant Professor, Department of Radiodiagnosis, All India Institute of Medical Sciences, Rishikesh, India

Email: sonalsaranmalik [at] gmail.com

Received: 26 February 2021 | Accepted: 02 April 2021

How to cite this article:

Anand R, Kumar S, Saran S. Coexisting molar and live twin pregnancy. Sudan J Paediatr. 2021;21(2):224–227.

https://doi.org/10.24911/SJP.106-1614318263

---

A 23-year-old female, Gravida 2, Para 1, presented to our clinic with amenorrhea, positive urine pregnancy test, excessive vomiting and vaginal bleeding. The patient did not document the last menstrual period date, but it was 3 months back. No other complaints were present. Her previous pregnancy was uneventful with normal vaginal delivery, and currently, the child is healthy. No abnormal past medical or surgical history was present. Her vitals were normal. On abdominal examination, the uterus was enlarged and measuring approximately 14-16 weeks of gestation. No other abnormalities were detected. Laboratory investigations indicated that beta human chorionic gonadotropin (hCG) was 2,56,721 mIU/ml, which was borderline high for the corresponding gestational age.A trans-abdominal ultrasound imaging (Figure 1) at our hospital discovered a normal live foetus of ~14 weeks gestational age with an adjacent mixed echogenic mass with a snowstorm appearance. The live foetus was normal and had no gross congenital anomalies. The placenta of the normal foetus was seen on the fundus and right lateral wall of the uterus. The mixed echogenic mass with snowstorm appearance was seen in the lower and left half of the uterine cavity and was seen covering the internal os. Both the ovaries were normal.

For further evaluation, magnetic resonance imaging (MRI) of pelvis was carried out (Figure 2). It demonstrated that the normal foetus was present with its placenta in the right half of the uterus. Placenta was fundal, without signal changes. No myometrial invasion was seen with the maintained myometrial interface. Adjacent to the foetus, there was a heterogeneous but predominantly T1 hypointense and T2 hyperintense multicystic mass in the left half of the uterus. No foetal parts were present in the latter suggestive of a complete molar pregnancy. The molar pregnancy completely covered the internal os with foci of blooming suggesting blood products. The lower uterine segment was entirely occupied by the molar mass displacing the normal foetus superiorly. No myometrial invasion was seen. No diffusion restriction was present to demonstrate any malignant transformation. Both ovaries were normal. Diagnosis of coexisting molar and live twin pregnancy was made.

The patient was managed conservatively. After a week, the patient underwent spontaneous abortion. Initially, she expelled molar tissue, followed by the foetus. No foetal parts were found in the molar tissue. Histological examination confirmed the imaging diagnosis. Now the patient is under follow-up with serial beta-hCG and ultrasound monitoring.

Complete mole is a precancerous condition in the spectrum of gestational trophoblastic diseases. It occurs due to abnormal fertilisation of a futile ovum without any chromosomes by a sperm with a healthy haploid set. As a result, there is abnormal non-invasive trophoblastic proliferation and swelling of chorionic villi. The incidence of complete twin molar pregnancy is uncommon, which varies geographically. However, molar pregnancy with the concurrent normal live foetus is extremely rare, occurring one in 20,000-100,000 pregnancies [1].

Figure 1. Trans-abdominal ultrasound showing a normal live foetus of 14 weeks gestational age having normal placenta (P) with an adjacent mixed echogenic mass (star) with a snowstorm appearance suggesting molar gestation.

Association of complete molar pregnancy with a live foetus is an unusual and atypical condition with only a few cases reported in the literature. It increases the risk of both foetal as well as maternal morbidity and mortality. Maternal complications are risks of haemorrhagic events and general complications like hyperemesis, preeclampsia, thyrotoxicosis and trophoblastic emboli. Hydatidiform moles can become invasive and malignant. Abortion, growth restriction and pre-term labour are the foetal complications related to this condition [1].

These molar placental tissues have abnormal swollen villous structures and can develop placental abscesses, which are catastrophic and challenging to manage [2]. The abnormal vesicular structures tend to occupy the lower uterine segment, which results in bleeding per vagina and on and off by shedding of vesicles [3]. As there is an increased tendency of molar pregnancies to recur with the risk of malignant transformation and distant metastasis, regular monitoring and follow-up are needed [4].

Figure 2. MRI showing a normal foetus with its placenta (P) in the right half of the uterus with a heterogeneous but predominantly T1 hypointense and T2 hyperintense multicystic mass in the left half of the uterus (star) suggesting molar gestation. Area of blooming can be seen overlying the internal os suggesting blood products (yellow circle).

Clinically diagnosing the condition is very difficult. Hence imaging plays a vital role in confirming the diagnosis. Scrutiny of the placental tissue is necessary to exclude a partial hydatidiform mole, diagnostically confirmed by visualisation of foetal parts [5]. The primary differential diagnosis is placental mesenchymal dysplasia and chorioangioma. The former is a benign vascular condition characterised by the enlargement of the placenta with multiple cysts. On the Doppler study, increased flow with high velocity is seen, which is extremely difficult to differentiate. Although hCG can be increased in this condition, predominantly alpha-fetoprotein (AFP) is raised. It is essential to differentiate this condition from the former as the perinatal prognosis is better in the placental mesenchymal dysplasia [6].Chorioangioma is usually focal but can vary in size. On ultrasound, they typically appear hypoechoic with cysts taking up the colour at Doppler imaging. AFP can be raised in this condition. It can be associated with congenital anomalies.

The three variants of twin gestation with molar pregnancy are:

1. Twin gestation of normal foetus and placenta with complete mole.
2. Twin gestation of normal foetus and placenta with partial mole.
3. Normal single foetus with the partial molar placenta (rarest) [7].

Previously, it was considered that termination of the pregnancy was the ideal method of management due to the risk of complications. However, with recent advances, the continuation of the pregnancy with the delivery of a healthy newborn is possible. It has been observed that hCG levels up to 400,000 IU/l are considered the best indicators for a better perinatal outcome [6].

For termination, the common consensus is dilatation and suction curettage, followed by chemotherapy. Beta-hCG levels should be normalised before discontinuing the chemotherapy. Methotrexate or actinomycin B is also commonly used for a molar pregnancy. Follow-up with beta-hCG is then done to ensure no recurrence of the disease [8]. The management of this condition is challenging due to the wide variety of maternal and foetal outcomes.

---

CONFLICTS OF INTEREST

The authors declare that there is no conflict of interest regarding the publication of this article.

---

FUNDING

None.

---

ETHICAL APPROVAL

Ethics clearance and approval of the study were granted by the ethics committee of our institute. Signed informed consent for participation and publication of medical details was also obtained from the patient. Confidentiality was ensured at all stages.

---

REFERENCES

1. Lin LH, Maesta I, Braga A, Sun SY, Fushida K, Francisco RPV, et al. Multiple pregnancies with complete mole and coexisting normal fetus in North and South America: a retrospective multicenter cohort and literature review. Gynecol Oncol. 2017;145(1):88–95. https://doi.org/10.1016/j.ygyno.2017.01.021
2. Suri S, Davies M, Jauniaux Twin pregnancy presenting as a previa complete hydatidiform mole and co existing fetus complicated by a placental abscess. Fetal Diagn Ther. 2009;26(4):181–4. https://doi.org/10.1159/000253272
3. Marcorelles P, Audrezet MP, Le Bris MJ, Laurent Y, Chabaud JJ, Ferec C, et al. diagnosis and outcome of complete hydatidiform mole coexisting with a live twin fetus. Eur J Obstet Gynecol Reprod Biol. 2005;118(1):21–7. https://doi.org/10.1016/j.ejogrb.2004.02.042
4. Dreyfus M, Tissier PE. National Cancer Institute: gestational trophoblastic diseases. J Gynecol Obstet Biol Reprod (Paris). 2000;29:125–30.
5. Fowler DJ, Lindsay I, Seckl MJ, Sebire NJ. Routine pre-evacuation ultrasound diagnosis of hydatidiform mole: experience of more than 1000 cases from a regional referral center. Ultrasound Obstet Gynecol. 2006;27:56–60. https://doi.org/10.1002/uog.2592
6. Braga A, Obeica B, Werner H, Sun SY, Júnior JA, Filho JR, et al. A twin pregnancy with a hydatidiform mole and a coexisting live fetus: prenatal diagnosis, treatment, and follow-up. J. Ultrason. 2017;17:299–305. https://doi.org/10.15557/JoU.2017.0044
7. Hassan SA, Akhtar A, Ud Deen Z, Khan M, Jamal S, Sohail S, et al. Sad fetus syndrome: partial molar pregnancy with a live fetus. Cureus. 2018;10(8):e3175. https://doi.org/10.7759/cureus.3175
8. Mccartie JD. Complete twin molar pregnancy. J Diagn Med Sonogr. 2002;18(2):100-103. https://doi.org/10.1177/875647930201800208