The kidney is not one large filter. Each kidney is made up of about a million filtering units called nephrons. Each nephron filters a small amount of blood. The nephron includes a filter, called the glomerulus, and a tubule. The nephrons work through a two-step process.
Generally speaking, first babies tend to engage from about 34 weeks to 36 weeks. However, some babies only engage once labour starts. Try not to worry, though. Even if your baby hasn't engaged by the time labour starts, in most cases, it's not a problem.
PALM BEACH GARDENS -- Early today, Palm Beach Gardens superstar tennis champ Serena Williams took to social media to announce that she's 20 weeks pregnant. It's been a big few months for Williams, who only 17 months ago announced her engagement to Reddit co-founder Alexis Ohanian.