MOTORISTS stuck in the traffic on Cairo’s Salah Salam highway need only look up for a clue to one cause of their misery. Looming above the road, a red digital ticker on the wall of the statistics agency displays Egypt’s population in real time: over 88m people, and counting. During one ten-minute jam in April the number went up by 21, tweets an aghast driver. Population growth in the Middle East, though higher than everywhere but sub-Saharan Africa, has been slowing thanks to falling fertility rates, the measure used by demographers for the number of children a woman is likely to have. But after 50 years of decline, the fertility rate in Egypt, the region’s most populous nation, is now back up to 3.5. That is lower than in Iraq and Yemen where it is over four, but above Saudi Arabia and Iran, which with 77m has the second-largest number of people in the region. Since infant mortality is falling and life expectancy increasing, the population will surely start growing faster.

That would be “catastrophic”, says one researcher in Cairo. By 2050 the UN thinks Egypt could be home to up to 140m people; and they live on just over 5% of its land, along the Nile and coast, since the rest is desert. Only with fewer than 55m people would the country escape being classed as “water poor” (with less than 1,000 cubic metres of water per person a year), says Atef al-Shitany, head of family planning at the health ministry. Shabby schools and hospitals are increasingly overburdened.

Hosni Mubarak, who ruled Egypt for 30 years from 1981, campaigned to reduce the fertility rate to 2.1, the level at which a population remains roughly stable. By 2005 it had almost halved to three, but it then stuck. Population policy has been adrift in the post-revolutionary chaos. So when Abdel-Fattah al-Sisi, who took power in a coup two years ago, appointed Egypt’s first population minister in March—Hala Youssef, a respected doctor—many guessed there would be a new push.

Yet in a country awash with prickly patriotism some officials are loth to accept that a soaring population could pose a problem. A national strategy published on Mr Sisi’s watch in October shied away from setting a target for the fertility rate, though some officials talk of 2.4 by 2030. Instead it emphasises informed choice. The government says it will improve family-planning services and encourage girls to stay in school longer. It is piloting cash transfers to some poor families in the hope they will no longer depend on their children as potential earners.

The use of contraception fell slightly during the period that the fertility rate rose, but not because of ignorance: surveys show that 99% of Egyptian women know about preventing pregnancy. Instead, Egyptians may just want bigger families. The rural poor still have the most children, though they have been receptive to reducing the number, driving the drop. By contrast “the urban middle class has always stuck to the three-child model,” says Dalia Abd al-Hameed of the Egyptian Initiative for Personal Rights, an NGO in Cairo.

Persuading couples to have fewer offspring is far trickier than handing out condoms. Few appreciate the state prying into their bedrooms; but in nearly all countries fertility tends to fall as people grow richer and women are better educated. In Iran it fell from 6.5 in 1980 to 1.9 today, because of rising incomes and a big push by the government for birth control. The government used to urge men to get vasectomies; now it is struggling to persuade women to have more children.

The increasing number of births will rob Egypt of some of its imminent demographic dividend—the economic advantage of having few old people and children relative to the number of working adults. “Meeting the demands of this population will require strong, sustained economic growth and redistributive policies,” says Jaime Nadal Roig, who heads Egypt’s branch of the UN’s population fund. Sadly for Egypt, making the economic indicators tick up fast enough is as hard as making the fertility rate go back down.