In December, when the mysterious novel coronavirus epidemic started, scientists raced to identify its transmission routes, and the possibility of infected pregnant women passing on the virus to their unborn babies was one of them.

While efforts to control the deadly virus continue, a preliminary study suggests pregnant women diagnosed with the COVID-19 do not pass on the virus to newborns.

Published in the journal Lancet on Wednesday, the study is based on a small sample size of nine infected pregnant women in their third trimester. Expecting mothers were admitted at the Zhongnan Hospital in Wuhan from January 20 to 31,  2020.

None of the patients died or developed severe complications during live births. "This is an important study because pregnant women can be particularly susceptible to respiratory pathogens and severe pneumonia because they are immunocompromised [low immunity]," said Huixia Yang, Peking University First Hospital, co-author of the study.

As the study involved a limited number of pregnancies, researchers feel more studies are required to support their confirmation.

According to professor Yuanzhen Zhang, Zhongnan Hospital of Wuhan University, lead author of the study, more clinical details are needed to confirm the transmission of novel coronavirus within the uterus.

"Nonetheless, we should continue to pay special attention to newborns born to mothers with COVID-19 pneumonia to help prevent infections in this group," Zhang added. 

All expecting mothers in the age range of 26 to 40 years had no underlying health condition and gave birth to healthy babies. Seven of them were delivered through cesarean section, and two developed minor complications.

Evidence from SARS and MERS outbreaks

Previous studies related to coronavirus outbreak leading to Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) in 2002 and 2012, respectively, show expecting mothers facing severe health complications.

A significant number of pregnant women infected with SARS or MERS suffered miscarriages, kidney failures, putting mothers and newborns under intensive care. Since the new strain of virus also belongs to the same family of coronavirus, it raised concern among doctors dealing with maternal and childcare.

A newborn in Wuhan infected with the new strain of coronavirus nearly 30-hours after the birth further sparked speculations over mother to child transmission of the virus.

The situation becomes more alarming, keeping in view the considerably high birth rate in Wuhan — the epicenter of the epidemic. More than 120,000 babies were born in the city last year. An estimate suggests more than 5,000 were born during the last 15 days in the city. 

Dr. Jie Qiao from Peking University Third Hospital, who was not involved in the study, said the new research helps in the understanding of clinical characteristics, pregnancy outcomes and transmission potential of COVID-19.

It's a valuable contribution to preventive and clinical practice in China and elsewhere under such emergent circumstances, Jie added.

(Top Image: A delivery man carries goods near a health checkpoint into an office building in Beijing, China Thursday, Feb. 13, 2020. /AP Photo)