Mexico City, Jun 23 (IANS): Mexican officials detected more than 200 pregnant women among the migrants who entered Mexico in the last four months over the southern border, which has been closed down this weekend by the National Guard.

"We have detected over 200, many of whom continued on their way while the pregnancies of others were so far along they had to be taken to General Hospital," a senior official told Efe news.

During this time more than a dozen babies have been born, all of them "Mexicans of foreign mothers", the official said with reference to the law that grants Mexican citizenship to anyone born in this country.

He said that among the pregnant women left at Mexico's southern border are citizens of Haiti, Guatemala, Honduras and also of the Congo.

The healthcare official said that by having children born in Mexico, parents have the right to obtain citizenship, which helps straighten out the nation's migratory status.

Meanwhile the National Guard has been deployed to all of Mexico's municipalities on the border with Guatemala, which has led to a diminishing flow of migrants, something Mexico is trying to achieve in order to keep the US from imposing tariffs on all its products.

On the banks of the Usumacinta River, the natural border between Mexico and Guatemala, the number of migrants has dropped considerably and only sporadic groups are to be seen trying to cross however they can.

According to regulations established by the National Institute of Migration, immigration procedures are slow and only allow the entry of foreigners with documents that clearly authorize their stay.