Women getting pregnant in Ruiru sub-county in Kenya are at great risk of delivering a disabled child compared to other parts of Kiambu County.
A study, the first of its kind in Kenya, says the place of conception may be associated to the child being born with physical disabilities.
“This information is important because in some cases potential parents can take precaution either before or soon after conception,” says Dr George Nyadimo Agot, the principal investigator.
Last year Dr Agot with senior colleagues at the University of Nairobi had investigated what they found to be increasing cases of birth defects in Kiambu County.
They had reported the county to have recorded 44 birth defects in every 100,000 births in 2014 but which had increased to 205 by 2018.
“This is a worrying trend,” the team of Dr Agot, a birth defects epidemiologist, Dr Marshal Mutinda Mweu and Prof Joseph Kibuchi Wang´ombe had reported.
“We went back to investigate, the geographical occurrences of these defects and their causes across Kiambu County,” said Dr Agot.
The new study has been carried out in 13 hospitals spread across the 12 subcounties of Kiambu County with Ruiru subcoutry found to have the highest number of children being born with defects.
On the other hand Kiambu sub-county which mainly constitutes the Kiambu town and adjacent areas had the lowest risk of birth defects.
Children conceived in Ruiru Sub County, the new study says are at highest risk of birth defects compared to pregnancies happening in other parts of Kiambu County.
“Women who got pregnant when residing in Ruiru sub-county were 5.28 times likely to give birth to children with defects compared to those who got pregnant residing in other sub-counties within Kiambu County,” says the study published in F1000 Research database.
On the other hand women who got pregnant when residing in Kiambu sub-county were 27 per cent less likely to give birth to children with defects compared to those who got pregnant residing in other sub-counties within Kiambu.
The study involved 408 children aged under five years with cleft lips and palates, limbs, clubbed hand and foot, skeletal, hydrocephalus and rectal as some of the reported deformities.
The team suggests the high rates of birth defects in the area may be genetic related. “Our study alluded to an increased risk of chromosomal abnormalities thus suggestive of the prevalence of birth defects of genetic origin in the county,” says the study. Chromosomes are an important part of your genes.
As a pointer to genetic causes, the authors tell of finding cases of similar defects among siblings in the same family who are also at risk of passing on the defects to their offspring.
“This was indeed evident in the study where four of the case subjects with clubfoot similarly reported clubfoot in their preceding siblings.”
The experts further point to cases of siblings suffering multiple but similar types of disabilities as evidence of genetic cause of their defects. This may include clubfoot, autism, deafness or Down syndrome in the same family and children.
“Compared to siblings without a history of birth defects, siblings with a history of birth defects were 7.65 times likely to be born with defects,” says the study.
Delayed maternal age
Although not established in the current study, the authors say birth defects related to genetic causes have been associated with women delaying childbirth beyond 35 years and lack of clinical genetic diagnostic services. “Such defects have also been reported in places with high rates of marriages among relatives.”
The team makes two key observations about Kiambu County: That a mother’s residence at the time of conception and having a history of siblings with birth defects are strongly associated with the formation of birth abnormalities.
The team suggests the establishment genetic screening services within antenatal clinics for early diagnosis counseling and treatment where possible.
“The services should include elective termination of pregnancies with anomalies where the law allows,” suggests the three senior lecturers.
By Gatonye Gathura
The study is available here: https://doi.org/10.12688/f1000research.50738.2