1. read and rewrite the paragraph in your own word. do not copythe text below use your own word. the concept of the originalparagraph should be retained.

We reviewed clinical records, laboratory findings, and chest CTscans for all nine pregnant women. All information was obtained andcurated with a customized data collection form. Two studyinvestigators (JG and XY) independently reviewed the datacollection forms to verify data accuracy.

Maternal throat swab samples were collected and tested forSARS-CoV-2 with the Chinese Center for Disease Control andPrevention (CDC) recommended Kit (BioGerm, Shanghai, China),following WHO guidelines for qRT-PCR.5–7 All samples were processedsimultaneously at the Department of Clinical Laboratory of ZhongnanHospital and State Key Laboratory of Virology/Institute of

Medical Virology, School of Basic Medical Sciences, WuhanUniversity. Positive confirmatory cases of COVID-19 infec- tionwere defined as those with a positive test result from eitherlaboratory.

Amniotic fluid samples from patients with COVID-19 pneumoniawere obtained via direct syringe aspiration at the time ofdelivery. Cord blood and neonatal throat swab samples werecollected immediately after delivery in the operating room.Additionally, breastmilk samples from patients with COVID-19pneumonia were col- lected after their first lactation. Evidence ofvertical transmission was evaluated by testing for the presence ofSARS-CoV-2 in these clinical samples. Sample collection wassuccessful in six cases (patients 2, 4–6, 8, and 9). Among thethree patients from whom sample collection was not successful,patient 1 was diagnosed after caesarean section, thus no sample wasobtained. Patients 3 and 7 underwent caesarean section at night,thus immediate sample collection was not possible. All samples wereprocessed at the State Key Laboratory of Virology/Institute ofMedical Virology, School of Basic Medical Sciences, WuhanUniversity, for further testing. Sample collection, processing, andlaboratory testing complied with WHO guidance.6 All samples, asdescribed above, were tested for SARS-CoV-2 by use of qRT-PCR withthe CDC recommended Kit. The test results were confirmed by nestedRT-PCR with designed primers. For the nested RT-PCR assay, totalRNA was extracted from samples by use of the TRIzol LS reagent(Invitrogen, Carlsbad, CA, USA), followed by reverse transcriptionby use of the one-step RT-PCR Kit (TaKaRa, Dalian, China). Primerswere designed on the basis of he sequence of Wuhan-Hu-1 (MN908947).Partial S segment sequences (nt21730-22458) were amplified withprimers: 5′-CTCAGGACTTGTTCTTACCTT-3′ and5′-CAAGTGCACAGTCTAC-AGC-3′.